Part I

Question 1: (a)
Rome and Turin occur 3 times, while Milan occurs 1 time. With the default
partitioner and 2 reducers, Rome and Milan are assigned to part-r-00000 and
Turin is assigned to part-r-00001. Hence, the two reducers emit 1 and 1.

Question 2: (c)
A.txt is read 3 times. The application has three actions depending on A.txt:
RDD_B.count(), the reduce action computing min_Value, and the reduce action
computing max_Value. No RDD is cached/persisted.

Exercise 1.2 - Number of instances of the reducer - Job 1: (c)
Any number >=1. The first job groups patches by operating system and the
computation can be parallelized by key.

Exercise 1.3 - Number of instances of the reducer - Job 2: (c)
Exactly 1. The second job selects the global maximum difference and applies the
alphabetical tie-break rule.
